Field Of The Invention
[0001] This invention is generally directed to a powered surgical tool that includes a sterilizable
handpiece and an unsterilzable, aseptic, power module. The tool of this invention
is configured so that the power module detects the type of handpiece to which the
module is attached and sources power as a function of the type of handpiece.
Background Of The Invention
[0002] In modern surgery, one of the most important instruments available to medical personnel
is the powered surgical tool. One form of a powered surgical tool is a handpiece in
which a motor is housed. Secured to the handpiece is a cutting attachment designed
for application to a surgical site to perform a specific medical procedure. Some powered
surgical tools are provided with drills, burs or reamers for cutting bores into tissue
or for selectively removing tissue such as bone. Other motorized powered surgical
tools are provided with saw heads. These tools separate large sections of hard and
soft tissue. A wire driver is a power tool that, as its name implies, drives a wire
into a patient, more particularly, a bone. Power tools are also used to perform other
functions in the operating room. For example, it is known to use a power tool to mix
the components that form a mass of surgical cement. Other powered surgical tools include
power generating units such as ultrasonic drivers or devices that emit photonic (light)
energy.
[0003] The ability to use powered surgical tools on a patient lessens the physical strain
of surgeons when performing medical procedures on a patient. Moreover, most surgical
procedures can be performed more quickly and more accurately with powered surgical
tools than with the manual equivalents that preceded them.
[0004] One type of powered surgical tool that is especially popular with some physicians
is the cordless, battery-operated powered surgical tool. As the name implies, this
tool has a battery that functions as the power source for the tool power generating
unit. This eliminates the need to provide the tool with a power cord connected to
an external-power source. Elimination of the power cord offers benefits over corded,
powered surgical tools. Surgical personnel using this type of tool do not have to
concern themselves with sterilizing a cord so the cord can be introduced into the
sterile surgical field or ensuring that, during a procedure, an unsterilized section
cord is not inadvertently introduced into the surgical field. Elimination of the cord
also results in the like elimination of the physical clutter and field-of-view blockage
a cord brings to a surgical procedure.
[0005] There are differences between conventional power tools and power tools designed to
perform surgical procedures. A power tool designed to perform a surgical procedure
must be able to withstand the rigors autoclave sterilization. In an autoclave sterilization
process, the tool is placed in a chamber in which the atmosphere is saturated with
water vapor (steam) the temperature can exceed 110°C and the pressure exceeding 290
torr. Internal components of the tool, including the electrical components of any
circuit, if left unprotected in and repeatedly exposed to this environment, corrode.
[0006] One solution to prevent this type of corrosion is to housing as many electrical conductive
components of the tool in sealed modules or sealed shells. The Applicant's
US Pat. No. 7,638,958/PCT Pub. No.
WO 2007/002180A2, the contents of which are explicitly incorporated herein by reference by reference,
discloses how many of the components associated with a motorized powered surgical
tool can be incorporated into a single sealed module.
[0007] The assembly of the above publications does a more than adequate job of protecting
many of the electrical components of a powered surgical tool from the adverse effects
of sterilization. However, over time the joints of the sealed module can breakdown.
Also, the motor, the rotor and windings, of this tool is not protected to the extent
the components in the sealed module are protected. Further, it can be expensive to
provide a tool with the protection provided by this sealed module.
[0008] Another solution to this problem is to divide the components of the tool into two
parts, one that is sterilized and one that is not sterilized. More specifically, this
type of tool includes a power module and a handpiece. The power module includes the
power generating unit, for example a motor. Also disposed inside the power module
are cells that store charge used to activate the power generating unit. The power
generating unit includes a control circuit. The control circuit regulates the activation
of the power generating unit. The body, the shell, of this power generating unit,
as well as the components internal to the body, are not designed to withstand the
sterilization process.
[0009] The second part of the tool is the handpiece. The handpiece includes a body or shell.
Internal to the handpiece body is a void for receiving the power generating unit.
A handpiece also includes some sort of transmission. The transmission is capable of
transmitting the power output by the power generating unit to the attached implement
that is applied to the patient to perform the desired procedure. Often the handpiece
includes some sort of coupling components. The coupling components facilitate the
releasable attachment of the implement to the transmission. The handpiece body and
the attached components are designed to withstand the rigors of the sterilization
process.
[0010] When a tool with an aseptic power module is prepared for use, the handpiece is sterilized.
The power module is placed in the closed void internal to the handpiece. This seals
the unsterilized power module from the environment around the patient. The tool is
then used in the same manner in which a sterilizable tool is used. The power generating
unit is actuated to cause the implement to perform the desired procedure on the patient.
[0011] A benefit of the above described type of tool is that only the handpiece and its
internal components need to be designed to withstand sterilization. This makes it
less expensive to provide this type of tool in comparison to a tool the whole of which
is subjected to sterilization. Further, since the aseptic power module of this tool
is not subjected to sterilization, there is no possibility that this module will,
as a result of being exposed to the sterilization process, malfunction.
[0012] While the above type of tool is useful, there are limitations associated with the
tool. Some of these limitations are due to the fact that many power surgical tools,
while similar in shape, are different in operation. For example, two motorized powered
surgical tools a surgeon may employ are a wire driver and a sagittal saw. Both tools
include a motor. The tools are designed to drive different implements. The wire driver
is designed to rotate a wire or a pin. A sagittal saw is designed oscillate a blade
back and forth in plane around an axis that extends through the plane in which the
blade moves. Difficulties can arise if one inadvertently place a power module designed
for use with the handpiece of one of these tools into the handpiece of the other tool.
[0013] One suggested solution to this problem is to provide a switch on the power module.
At one point during the process of assembling the tool for use is that the switch
is manually set to indicate the type of handpiece to which the power module is coupled.
A disadvantage of this solution is that it requires the individuals preparing the
tool for use to properly set the switch.
Summary Of The Invention
[0014] The invention is related to a new and useful surgical power tool. The power tool
of this invention includes both a sterilizable handpiece and an aseptic power module.
The tool of this invention is designed so that the power module automatically sources
power to different handpieces as a function of the power requirements specific to
each handpiece.
[0015] The handpiece of the tool of this invention includes a data tag. The data tag stores
data identifying which the specific type of handpiece from plural different types
of handpieces. The power module includes a reader and a controller. The reader reads
the data from the handpiece data tag. The controller receives the signal from the
reader that identifies the type of handpiece. Based on the type of handpiece, the
controller the power generating unit internal to the power module to source power
appropriate to the type of handpiece to which the module is attached.
[0016] In some preferred versions of the invention the handpiece data tag is integral with
the latch used to hold the power module to the handpiece. The absence/presence of
the data signal from the data tag is further employed by control circuit as an indicia
that the power module is properly coupled to the handpiece and the tool is ready for
use. Only after the control circuit makes determinates the lid is in a latched state
does the control circuit actuate the tool power generating unit.
[0017] In some preferred version of the invention, the handpiece data tag consists of a
set of one or more specifically placed magnets. The power module data reader consists
of one or more sensors. Each sensor selectively outputs a signal as a function of
the presence/absence of a magnet. In some versions of the invention, the sensor outputs
a signal as a function of the strength of the sensed magnetic field.
[0018] In some versions of the invention, the power module power generating unit is a motor.
In these versions of the invention, the handpiece transmission is a gear train that
transfers the mechanical energy of the motor to the attached energy applicator or
implement.
Brief Description Of The Drawings
[0019] The invention is pointed out with particularity in the claims. The above and further
features and benefits of the invention are understood from the following Detailed
Description taken in conjunction with the accompanying drawings in which:
Figure 1 is a perspective view of a surgical tool of this invention;
Figure 2 is an exploded view of the components of this invention including a depiction
of how a power module is fitted to a handpiece;
Figure 3 is a cross sectional view of the tool of the invention;
Figure 4 is a cross sectional view of the handpiece;
Figure 5 is an exploded view of the handpiece lid;
Figure 6 is a perspective view of the power module;
Figure 7 is a front plan view of the power module;
Figure 8 is a rear plan view of the power module;
Figure 9 is a left side plan view of the power module;
Figure 10 is a right side plan view of the power module;
Figure 11 is a top plan view of the power module;
Figure 12 is a bottom plan view of the power module;
Figure 13 an exploded view of the components internal to the power module;
Figure 14 is a cross sectional view of the power module;
Figure 15 is a perspective view of how the sensors are mounted to the base of the
power module;
Figure 16 is a block diagram of the electrical circuit of the power module;
Figures 17A and 17B form a flow chart of the operation of the tool of this invention;
Figure 18 is a perspective view of an alternative handpiece that forms a tool of this
invention;
Figure 19 is exploded view of how a key can be fitted to the power module to place
the module in a maintenance mode.
Detailed Description
I. OVERVIEW
[0020] A powered surgical tool 30 of this invention is now generally described by reference
to Figures 1-3. Tool 30 includes a handpiece 40 in which a power module 180 is removably
seated. Internal to the power module 180 is a power generating unit. In the described
version of the invention, the power generating unit is a motor 290. Also disposed
in the power module 180 are cells 270 and a controller 320. Cells 270 provide the
charge for energizing the motor 290. Controller 320 selectively applies current to
the motor 290 to regulate the actuation of the motor.
[0021] Handpiece 40 includes components to which the power output by the handpiece motor
290 is applied. One of these components is a drive spindle 136. Since the described
surgical tool 30 is motorized surgical tool, the tool includes a coupling assembly
170 generally represented by a ring. Coupling assembly 170 releasably holds an energy
applicator or a front end attachment to the handpiece 40. An energy applicator, for
the purposes of this invention, is a device that is applied to the patient to accomplish
a surgical task. Energy applicators attached to motorized surgical handpieces include
drill bits, saw blades, reamers and burs. An energy applicator for this invention
is also understood to be medical device that is driven into a patient for either permanent
or temporary implantation. These types of devices include wires, pins and screws.
In some versions of the invention, the coupling assembly is configured to removably
receive a front end attachment. The front end attachment is the actual device that
engages and drives the energy applicator. This allows a single tool to be used to
drive different types of energy applicators.
[0022] Handpiece 40 also includes at least one control component. In the depicted version
of the invention, there are two control components, triggers 152 and 154.
[0023] When use of the tool 30 is desired, one or both triggers 152 and 154 is/are selectively
depressed. Sensors 302 and 304 (Figure 13) internal to the power module 180 monitor
whether or not triggers 152 and 154 are depressed. When a trigger 152 or 154 is depressed,
the associated sensor 302 or 304, respectively, outputs a signal representative of
the trigger state to the controller 320. In response to receipt of this signal, the
controller 320 regulates the application of current to the motor to cause the desired
actuation of the motor 270. More particularly, current is applied to the motor to
cause the actuation of the motor that results in the actuation of the energy applicator
desired by the surgeon.
II. HANDPIECE
[0024] Initially, it should be understood, that the components forming the handpiece 40
are able to withstand the rigors of autoclave sterilization or other sterilization
process to which the handpiece may be exposed. For a component to withstand the rigors
of autoclave sterilization the component should be able to withstand exposure to an
environment wherein the temperature is in excess of 105°C, supersaturated steam (water
vapor) at a pressure of 2 Bars is present.
[0025] Handpiece 40, as now described by Figures 1-4, as includes a shell 42. Shell 42 is
the body or housing of the handpiece 40. The depicted shell 42 is shaped to have a
base 44. In a plane perpendicular to the plane of Figure 3, base 44 is generally rectangular
in shape. The bottom end of base 44 is open. Base 44 is formed so as to have two hinge
knuckles 47 (one identified) that extend proximally and slightly downwardly from the
proximal end of the base. While not seen, handpiece 40 is formed so that the bottom
end of the base 44 is has a rim that defines the outer perimeter of the opening into
the base 44. This rim is stepped inwardly from the outer surface of the base 44. Base
44 is formed to have a slot 45, identified in Figure 4. Slot 45 extends inwardly from
the inner surface of the distally directed panel of the base 44. The shell is formed
so that slot 45 is located a relatively short distance, less than 0.5 cm, above the
open end of the base 44. Slot 45 does not extend through the whole of the panel in
which the slot is formed.
[0026] A handgrip 46, also part of shell 42, extends upwardly from base 44. In the depicted
version of the invention, handgrip 46 does not rise from the center of the base 44.
Instead the handgrip 46 rises from a top of the base along a top-to-bottom longitudinal
axis that is distally forward of the center of the top of the base 44. (Here "distal"
is understood to mean away from the person holding tool 30, towards the site to which
the attached energy applicator is applied. "Proximal" is understood to mean towards
the person holding the tool 30, away from the site to which the attached energy applicator
is applied.). A barrel 48, also part of the shell 42, is located above handgrip 46.
Barrel 48 has a proximal-to-distal longitudinal axis that is generally perpendicular
to the top-to-bottom perpendicular longitudinal axis through handgrip 46. Shell 42
is formed so that barrel extends both proximally rearward from and distally forward
from the handgrip 46.
[0027] The particular handpiece 40 illustrated is a device known as a dual trigger rotary
handpiece. A coupling assembly 170 is mounted to the front end of barrel 48. This
type of handpiece, is designed to releasably hold another surgical tool called a front
end attachment (not illustrated). Coupling assembly 170 has an open front end, not
identified, that is dimensioned to receive the front end attachment. The front end
attachment is removably held to the handpiece shell 42 by coupling assembly 170. Internal
to the front end attachment is a drive shaft. The front end attachment drive shaft
is dimensioned to releasably engage and be driven by the handpiece drive spindle 136.
One type of front end attachment is a chuck. The chuck is configured to releasably
hold and transfer rotationally power to a rotating energy applicator such as a drill
bit. Another type of front end attachment is a wire driver. A wire driver holds an
energy applicator constructed to be driven into the patient for either permanent or
temporary implementation. Wires and pins are two species of this type of energy applicator.
The structure of these front end attachments and energy applicators is outside the
scope of the present invention.
[0028] The open end of base 44 leads to a void, compartment 52, in the shell 42. The shell
42 is formed so that compartment 52 extends through the base 44 and handgrip 46. Compartment
52 opens up into a void 54 that extends through the shell barrel 48. Void 54 extends
between the proximal and distal end of the barrel 48. The top of the shell 42 is formed
with a keyhole shaped opening 56 (Figure 2). The wide circular portion of opening
56 opens into the distal end of the barrel void 54. Coupling assembly 170 seats in
the circular portion of opening 56. The oval portion of opening 56, the narrow width
portion, opens into the portion of compartment 52 immediately below void 54. Shell
42 also is formed with two coaxial circular holes 58. Holes 58 extend through the
opposed sides of the shell 42. Holes 58 open into the portion of compartment 52 below
void 54.
[0029] A lid 62, now described by reference to Figures 4 and 5, is pivotally attached to
shell base 44 adjacent the bottom opening into compartment 52. Lid 62 includes a generally
planar plate 63. A rim 64 extends upwardly from and around the outer perimeter of
plate 63. Collectively, the components of tool 30 are dimensioned so that the lid
62 can seat over the open end of shell base 44, and when the lid is so seated, the
lid rim 64 seats in the stepped space located immediately outwardly from handpiece
shell rim. Plural knuckles 65, one seen in Figure 5, extend proximally rearward from
the proximally directed face of lid rim 64. When handpiece 40 is assembled, the lid
knuckles 65 are aligned with the handpiece shell knuckles 47. Lid 62 is pivotally
connected to the shell base 44 by a pin 66 that extends through coaxial bores in the
shell and lid knuckles 47 and 65, respectively.
[0030] Two parallel ribs 67, one identified, extend upwardly from the inner surface of lid
plate 63. A raised island 68 also extends upwardly from the inner surface of lid 62.
Island 68 has rectangular section and a circular section, (individual island sections
not identified). The island rectangular section is located between and is spaced inwardly
from ribs 67. The island circular section has is located distally forward from the
island rectangular section. The island circular section has a diameter that is greater
than the side-to-side width across the rectangular section. Lid 62 is further formed
to so that the rectangular section of island 68 is formed with a recess 69. Further,
an opening 70 extends through the circular section of the island 68.
[0031] A gasket 73 formed of compressible material such as silicone is seated on the inner
surface of lid plate 63. Gasket has two ribs 74. The components of the handpiece 40
are formed so that when the gasket 73 is disposed over the lid plate 63, the gasket
ribs 74 are located above the lid ribs 67. While not seen, the outwardly directed
face of the gasket is formed with openings. These openings project into gasket ribs
74 and are dimensioned to receive the lid ribs 67. Thus, as part of the process of
assembling handpiece 40, gasket 73 is seated on lid plate 63 so that the lid ribs
67 seat in the gasket ribs 74. The seating of these ribs together facilitates proper
seating of gasket 73 on lid 62. The gasket 73 is further formed to have a center opening
75. Gasket center opening is dimensioned to receive lid island 68.
[0032] A plate 79, formed from stainless steel, is disposed over the surface of gasket 73
opposite the lid 62. Plate 79, like gasket 73, has a shape that is similar to the
shape of lid plate 63. A difference between gasket 73 and plate 79 is that plate 79
is shorter in both length and width than gasket 73. Plate 79 is formed with a number
of openings. Two of the openings, openings 80, (one opening 80 identified) are each
dimensioned to receive a separate one of the gasket ribs 74. More specifically, it
should be understood that the gasket ribs project up approximately 3 mm from the upwardly
directed face of plate 79. Plate 79 is formed with an opening 81 that is generally
in the shape of a rectangle with rounded corners. When handpiece 40 is assembled,
plate opening 81 is in registration over recess 69 formed in lid 62.
[0033] A fourth opening in plate 79 is opening 82. Opening 82 is generally circular in shape.
When the handpiece is assembled, opening 82 is in registration with opening 70 formed
in lid 62. Plate 79 is formed with plural additional openings 83, only one identified.
Openings 83 receive the fasteners 84 that hold plate 79 to lid 62. Fasteners 84 extend
into threaded closed end bores 85 formed in the lid 62.
[0034] Plate 79 is further formed have two arcuately shaped beams 86. Beams 86 extend from
a tab 85 that projects into opening 82. The beams 86 extend from opposed sides of
tab 85. A toe 87 extends outwardly from the end of each beam 86. Toes 87 are generally
directed towards the center of opening 82. Owing to the material from which plate
79 is formed, beams 86 are able to flex relative to tab 85. Plate 79 is further formed
to have a tab 88 that extends into opening 82. The plate 79 is formed so that tab
88 is located between toes 87. Tab 88 extends into open
[0035] A latch knob 90 and latch plate 101 are rotatably mounted to the handpiece lid 62.
The latch knob 90 is shaped to define a core 91 that is generally cylindrical in shape.
The outer diameter of core 91 is such that the core can rotate in lid opening 70,
gasket opening 75 and plate opening 82. While core 91 is generally cylindrical, the
core is formed with a step 92 that extends radially inwardly from the outer perimeter
of the core. Step 92 faces the portion of the core that is directed upwardly, towards
the handpiece barrel 48. Detents seen at the ends of the core are for manufacturing
purposes only (detents not identified). The core 91 is further formed so that arcuately
spaced from step 92 are two detents 93. Detents 93 extend inwardly from the outer
cylindrical surface of the core. Each detent 93 can receive a separate one of the
toes 87 integral with beams 87. When handpiece 40 is assembled, plate beams 86 seat
against the curved outer surface of the core 91. Plate tab 91 seats in the space immediately
above core step 92.
[0036] Latch knob 90 also has a lip 95. Lip 95 extends radially outwardly and circumfentially
around the outer perimeter of knob core 91. The lip 95 extends around the outermost
portion of the core 91. Upon assembly of handpiece 40, lip 95 seats in a step (not
illustrated that extends inwardly from the outer surface of lid 62. This step extends
circumferentially around lid opening 70.
[0037] Four closed end bores extend inwardly from the inner face of core 91. Two bores,
bores 96, are formed with threading (not illustrated). Two bores, bores 97 are smooth
walled.
[0038] A magnet 98 is seated in one or both of the bores 97. In the illustrated version
of the invention, a magnet 98 is seated in both bores 97.
[0039] The latch plate 101 is secured over the inner face of core 91. The latch plate 101
is formed of magnetically permeable material such as 300 stainless steel. Latch plate
101 has a generally disc shaped main body 102. An arcuately shaped lip 103 extends
radially outwardly from one section of the plate body 102. Lip 103 projects radially
beyond the main body 102 so as to extend outwardly beyond core 91 of latch knob 90.
In the illustrated version of the invention, the surface of lip 103 directed to the
lid 62 is tapered. Extending arcuately from one end of the lip 103 to the opposed
end, the thickness of the lip increases. Two holes 104 (one identified) extend through
plate body 102.
[0040] Two fasteners 105 secure the latch plate 101 to the inner face of lid core 91. Each
fastener 104 extends through one of the holes 104 into one of the threaded bores 96
formed in knob 90d. As a consequence of the latch plate 101 being secured to the exposed
inner face of knob core 91, the latch plate 101 holds magnets 98 in bores 97 internal
to the knob 90.
[0041] Returning to Figures 2-4, it can be seen that the handpiece drive spindle 136 is
part of a transmission 120. Transmission 120 includes a case 122. Case 122 is designed
to fit in shell void 54. A portion of case 122 also seats in the oval portion of shell
opening 56 that opens into compartment 52. Two spindles, an input spindle 124 and
the drive spindle 136, are parts of transmission 120 that are rotatably mounted to
case 122. Input spindle 124 has a base 126 that is located below the case 122. The
input spindle 124 thus projects into compartment 52. Base 126 is formed with a closed
end bore 128 that extends upwardly from the bottom of the base. Not identified are
the teeth that extend inwardly from the inner surface of base 126 that define bore
128. Not illustrated are the bearing assemblies that rotatably hold the input spindle
124 to case 122. The head of the input spindle 124 is a bevel shaped gear 130.
[0042] Drive spindle 136 is mounted to case 122 so that when handpiece 40 is assembled,
drive spindle is centered on a longitudinal axis that is parallel to, if not collinear
with the longitudinal axis through the shell void 54. Not identified are the bearing
assemblies that rotatably hold the drive spindle 136 to the case 122.
[0043] The drive spindle 136 is formed to have features that facilitate the releasable coupling
of the front end attachment to the spindle. In the illustrated version of the invention,
these features include a head 138 that extends forward of case 122. Head 138 is formed
to have a bore 140 that extends proximally rearward from the distal end of the head
138. Teeth (not identified) extend inwardly from the inner surface of the head that
defines bore 140. The head is thus designed to receive toothed shaft integral with
the energy applicator or front end attachment. The engagement of the shaft causes
the implement or attachment shaft to rotate with the drive spindle 136.
[0044] A planetary gear assembly 142, also part of transmission 120, connects the input
spindle 124 to the drive spindle 136. The planetary gear assembly includes an input
shaft 144. A bevel gear 146 is located at the proximal end of shaft 144 with a bevel
gear 142. Gear 146 engages input spindle gear 130. The engagement of gears 130 and
146 causes the drive spindle 136 to rotate upon the rotation of the input spindle
124. Planetary gear assembly 142 reduces the rotational speed of the drive spindle
136 relative to the input spindle 124 so as to increase the torque the drive spindle
can output.
[0045] Also mounted to shell 40 are triggers 152 and 154. Triggers 152 and 154 are moveably
attached to a frame 150. Frame 150 is seats in an oval portion of case 122. This oval
portion of case 122 seats in the portion of compartment 52 immediately proximal to
the oval portion of opening 56.
[0046] Each trigger 152 and 154 includes a generally cylindrical barrel 156 (one barrel
identified in Figure 2). Barrel 156 is the portion of each trigger 152 and 154 slidably
mounted to frame 150. A head 158, shaped as a finger grip, is disposed over the distal
free end of the barrel. A magnet is mounted to the proximal end of the barrel. For
the purposes of understanding this invention, magnet 162 is the magnet integral with
trigger 152. Magnet 164 is the magnet integral with trigger 154. A spring 160 disposed
between an interior surface of frame 150 and each barrel 156 exerts a force on the
barrel to urge the barrel distally forward. The force exerted by spring 160 can be
overcome by finger force.
[0047] Handpiece 40 also includes a rod shaped mechanical slide 168. Slide 168 is mounted
to frame 150 and has ends that extend out of shell openings 58. Slide 168 is selectively
positioned to prevent the unintended depression of triggers 152 and 154. The means
by which slide 168 operates and the assembly employed to hold triggers 152 and 154
to frame 150 are not part of the present invention. An understanding of some of these
assemblies are disclosed in
US Pat. No. 7,638,958/PCT Pub. No.
WO 2007/002180, the contents of which is explicitly incorporated herein by reference.
III. POWER MODULE
[0048] The power module 180 of this invention is typically formed out of aseptic components.
This means that the components of the power module 180, including the components forming
the module shell or housing, are not able to withstand the sterilization process to
which the handpiece 40 can be exposed.
[0049] The power module 180, now described with reference to Figures 6-14, includes a base
182 and a cap 204 that, when assembled together collectively form the housing or shell
of the module. Base 182 is rectangular in shape. The base 182 includes a bottom plate
184. Opposed side panels 186 extend upwardly along the proximally to distally extending
sides of the base. A front panel 188 extends upwardly from the distal end of plate
184 between the side panels 186. A back panel 190 extends upwardly from the proximal
end of plate 184 between the side panels 186.
[0050] A U-shaped bar 198 with a semicircular bend in the middle is pivotally mounted to
the outer face of bottom plate 184. Bar 198 partially seats in a recess 196 formed
in the outer surface of the bottom plate 184. Bar 198 functions as a handle to facilitate
the insertion and removal of the power module 180 to and from the handpiece 40.
[0051] Cap 204 includes a rectangular lid 206. Lid 206 is dimensioned to seat over the open
end of base 182. Lid 206 is formed to have openings 208 located along the proximal
edge. Posts 209 (two identified) extend downwardly from lid 206. A rim 207 forms the
outer perimeter of the lid. Rim 207 is the portion of the lid that actually abuts
the top end of base 182.
[0052] The cap 204 is further formed to have a tower 210 that extends upwardly from lid
206. The tower 210 subtends a cross sectional area, in planes perpendicular to the
top-to-bottom longitudinal axis of the power module, that is less than the area subtended
by base 184 and lid 206. The cap 204 is formed so that the tower 210 does not extend
from the center of lid 206. Instead, the tower 210 is located towards the distal front
end of the lid 206. Cap 204 is formed so that tower 210 has a primary section 212.
Tower primary section 212 has a shape that in cross section, in a plane perpendicular
to the plane of Figure 9, can be described as approximately rectangular with rounded
corners. Tower primary section 212 occupies approximately 55 to 70% of the total length
of the tower 210.
[0053] The topmost portion of the tower 210, the portion above the primary section 212,
is head 214. The side and rear longitudinal panels of head 214 are recessed inwardly
relative to the adjacent side and rear panels of the tower primary section 212. The
top of head 214 is formed with a downwardly extending bore 216. Bore 216 has a diameter
that is dimensioned to receive the handpiece input spindle 124 so the input spindle
can freely rotate in the bore. A slot 218 extends downwardly along the proximally
directed panel of head 214. Slot 218 opens into bore 216.
[0054] Tower 210 is further formed to have two outwardly protruding ribs. A first rib, rib
226, extends proximally outward from the proximal panel of the tower primary section
212. Rib 226 extends up from lid 206 approximately 40 to 60% of the total length of
the tower primary section 212. The second rib, rib 228, extends distally forward from
both the primary section 212 and head 214 of the tower 210. Rib 228 extends upwardly
from lid 206 and extends along the whole of the length of the tower primary section
212. Rib 228 extends over approximately the bottom 20 to 30% of the tower head 214.
[0055] Tower 210 is further formed so that the distally directed panel 227 of the tower,
the panel located above rib 226, is located proximally relative to the distal edges
of the side panel of the tower (side panels not identified). Panel 227 and the adjacent
portions of the side panels that extend forward of panel 227 define a recess 229 in
the front of tower 210. A boss 230 extends outwardly from panel 227 into recess 229.
[0056] Fasteners 232 seen in Figure 13, secure base 182 and cap 204 together to form the
housing or shell of the power module 180. The fasteners 232 extend through openings
in the base bottom panel (openings not illustrated) into lid posts 209.
[0057] Disposed inside base 182 is a circuit board 240. Circuit board 240 supports the components
that form controller 320. Also secured to circuit board are plural contacts 266. When
the power module 180 is assembled, contacts 266 are accessible through lid openings
208. Contacts 266 are contacts over which current is sourced to the cells 270 for
storage. Contacts 266 also serve as contacts over which data and instructions are
written to the controller 320 and over which the controller reads out data.
[0058] Secured to the undersurface of the circuit board 240 are cells 270. Cells 270 are
rechargeable cells capable of holding a charge. Cells 270 may often be NiCad or Lithium
Ion cells. Cells 270 are typically connected together. The type of connections between
the cells, serial or parallel, is not part of the present invention. Given that the
cells 270 are connected together, the cells are sometimes referred to as a cell cluster.
[0059] From Figure 15 it can be seen that two U-shaped brackets 272 extend downwardly from
circuit board 240. Brackets 272 suspend cells to the undersurface of the circuit board
240.
[0060] A circuit board 278 is secured to the bottom surface of the distally located bracket
272. Circuit board 278 has an exposed surface that is directed to the inner surface
of power module bottom plate 184. Two sensors 286 and 288 are mounted to the exposed
surface of circuit board 278. Sensors 286 and 288 are able to detect the presence/absence
of localized magnetic fields. In one version of the invention, sensors 286 and 288
are each a Hall sensor. Tool 30 of this invention is constructed so that sensors 286
and 288 are positioned so that when latch knob 90 is in the fully latched position,
each sensor 286 and 288 is located immediately above a separate one of the bores 97
formed in the latch knob.
[0061] Returning to Figures 13 and 14, it can be seen that power module motor 290 is also
mounted to the upper surface of the circuit board 240. The motor 290 is mounted in
the cap tower 210. An output shaft 294 is connected to the motor rotor to rotate upon
rotation of the motor rotor. Power module 180 is constructed so that the free end,
the head, of the output shaft 294 is disposed in tower bore 216. The head of output
shaft 294 is formed with features that facilitate the releasable engagement of the
shaft 294 with the handpiece input spindle 124. In the illustrated version of the
invention the engagement features are teeth (not identified).
[0062] The power module 180 includes two additional sensors, sensors 302 and 304 that are
disposed in recess 229. Sensors 302 and 304 are configured to monitor the actuation
of triggers 152 and 154. In the described version of the invention, sensors 302 and
304 are Hall effect sensors. Sensors 302 and 304 are mounted to a circuit board 308
seated in recess 229. A ribbon cable 306 extends from circuit board 240 to circuit
board 308. Cable 306 includes the individual conductors (not illustrated) that establish
the electrical connections required to connect sensors 302 and 304 to the other control
components integral with the power module 180. Cable 306 extends through the opening
between recess 229 and the void internal to tower 210.
[0063] When the power module 180 is assembled, the circuit board 308 is seated in the tower
recess 229 so the circuit board seats over boss 230. Not identified is the hole in
the circuit board 308 in which boss 230 is seated. A plate 310 formed from magnetically
permeable material such as a plastic polymer is seated over the tower recess 229.
A threaded fastener 312 extends through an opening in plate 310, the hole in the circuit
board and into the tower boss 230. Fastener 312 holds both circuit board 308 and plate
310 to the tower 210.
[0064] Figure 16 provides a view of the fundamental components of power module that control
the actuation of motor 290. Specifically, mounted to circuit board 240 is the controller
320. Controller 320 selectively ties the windings of motor 290 to either the positive
or negative terminals of the cluster of cells 270 to cause the actuation of the motor.
In Figure 16 the controller 320 is shown as a single block component. This is for
purposes of illustration only. It should be understood that the controller 320 typically
includes plural components. Typically, these components include: a signal processor
that includes a memory with preloaded instructions; and switching components that
selectively tie the cells 270 to the power generating unit, motor 290. As discussed
below though, it should be understood that the controller is able to: receive signals
indicating the specific type of handpiece to which the power module is attached; and,
based on the handpiece type signals, cause the motor to run in a state that is appropriate
for that handpiece. One such controller that comprises a number of different components
is disclosed in the incorporated by reference
US Pat. No. 7,638,958/PCT Pub. No
WO 2007/002180. The controller of this document includes a digital signal processor able to regulate
motor operation based on a set of instructions loaded in the processor memory. This
controller also includes a set of high voltage drivers. The drivers selectively tie
the windings of the motor to either the positive or ground terminals of the cluster
of cells 270.
[0065] As inputs, controller 320 receives the signals output by the handpiece detect sensors
286 and 288. Controller 320 also receives the signals asserted by the trigger state
sensors 302 and 304. While not illustrated, it should be understood a bias current
is applied to each of sensors 286, 288 302 and 304. Controller 320 regulates the application
of the bias currents to the sensors.
[0066] Controller 320 is not just connected to cluster of cells 270 to regulate the application
of current to the motor 290. The controller 320 is also connected to the cells 270
to receive current from cells. This is the current that energizes the electrically
active components of the controller 320.
[0067] Cells 270 is shown as being connected to a single contact 266. This is to represent
that current is sourced to the cells through the contacts 266. Controller 320 is also
shown as being connected to a single contact 266. This to represent that instructions
are written to the controller 320 and data are written out of the controller through
the contacts 266.
IV. OPERATION
[0068] The operation of tool 30 of this invention begins with the sterilization of the handpiece
40 and charging of the power module 180. The means by which the handpiece 40 is sterilized
is not part of the present invention. Generally, though a process by which a surgical
tool can be sterilized to the appropriate sterilization assurance level may be employed.
The handpiece 40 may be subjected to an autoclave sterilization process. Alternatively,
the handpiece may be exposed sterilants other than steam. These sterilants include
vaporized hydrogen peroxide or vaporized ethylene oxide.
[0069] Power module 180 is charged by placing the module in a charger able to source current
to the cells 270. The current is sourced from the charger by contacts integral with
the charger that are connected to power module contacts 266.
[0070] Absent any other event, the power module is normally in a sleep state as represented
by step 330 of Figure 17A. When the power module is in the sleep state, the controller
is a lower power mode. This means only the components required to maintain the power
module 180 in this mode are energized. Thus, when the power module is in the sleep
state, bias currents are not applied to the sensors 286, 288, 302 and 304. Other components
that may not be energized when the power module 180 is in the sleep state are driver
circuits that tie the motor windings to the terminals of the cell cluster. When controller
320 is in the sleep state, the controller draws the smallest amount of current of
the power module operating states.
[0071] When the controller is in the sleep state it periodically wakes up and enters a tool
check state, step 332. When the controller 320 enters the tool check state the controller
applies the bias currents to sensors 286 and 288 needed to activate these sensors.
Signal processing components internal to the controller 320 needed to evaluate the
signals from sensors 286 and 288 are also turned on. It should thus be appreciated
when the controller is in the tool check state, the controller draws more current
than when in the sleep state.
[0072] When controller 320 is in the tool check state, the controller monitors the signals
output by sensors 286 and 288. If the power module has not been placed in a handpiece
40 and the handpiece lid has not been properly latched, there should not be magnetic
fields in the vicinity of either sensor 286 or sensor 288. The signals output by sensor
286 and 288 indicate that no such fields are present. Step 334 represents the controller
evaluating the signals from sensors 286 and 288.
[0073] If the evaluation of step 334 tests negative, no magnetic fields detected adjacent
either sensor 286 or 288, controller 320 interprets these data is indicating that
the power module has not been properly coupled to a handpiece 40. As represented by
the loop back to step 330, the controller 330 returns the sleep state. The application
of the bias currents to the sensors 286 and 288 is negated.
[0074] In some versions of the invention, the controller 320 transitions from the sleep
state to the tool check state once every 100 to 500 milliseconds. Each time the controller
320 enters the tool check state, the controller stays in the state approximately 5
to 10 milliseconds.
[0075] To continue the process of configuring a tool of this invention for use, the power
module 180 is inserted in the handpiece 42. The shell handgrip 46 is asymmetrically
located relative to the shell base 44. The power module tower 210 is asymmetrically
located relative to the module base 182. Owing to the asymmetry of these components,
the individual inserting the power module in the shell inherently tends to inserts
the power module in the shell in the correct orientation.
[0076] Upon inserting the power module 180 in the handpiece, the arcuate portion of bar
198 seats in lid recess 69
[0077] As a result of the insertion of the power module 180 in the shell 42, the head of
module output shaft 294 engages base 126 of the handpiece input spindle 124. Also,
at this time, sensor 302 enters into a position in which the sensor is in close proximity
to trigger magnet 162. Sensor 304 enters into a position in which the sensor is close
proximity to trigger magnet 164.
[0078] Lid 62 is then rotated closed over the open end of shell base 44. The arc around
which lid 62 is rotated is limited by the abutment of the plate tab 88 against the
opposed surfaces of the lid that define the sides of the space above step 92. When
the lid 62 is in the fully unlatched state, a toe 87 integral with one of the beams
86 seats in the adjacent detent. When the lid is in the fully latched state, the toe
87 integral with the other beam seat in the second detent. The changes in the resistance
to the rotation of the lid as a result of the seating/unseating of the toes 87 in
detents 92 provides a tactile indication of the latched/unlatched state of the lid
64. The rotating of latch knob 90 to the latched position completes the process of
coupling the power module to the handpiece. As a consequence of the rotation of the
latch plate lip 103, the lip presses against the adjacent lip of the shell base. Owing
to the dimensioning of the components, lip 103 of latch plate 102 rotates into slot
45 formed in the handpiece shell base 44. Owing to the rotation of the tapered surface
of lip 103 against the adjacent surface of the shell base that defines slot 45, the
rotation of the latch plate drives the lid against the shell base. More particularly,
the perimeter of the gasket 73, the portion of the gasket that extends outwardly from
plate 79, is driven against the bottom edge surface of the shell rim that defined
the open end of the shell base 44. The compression of gasket 73 seals the power module
180 in the handpiece shell 42. Gasket ribs 74 press against the undersurface of the
base of the power module. Gasket ribs 74 thus function as a shock absorbers that prevent
the movement of the power module 180 in shell compartment 52.
[0079] The rotation of latch knob 90 to the fully latched state also places a first one
of the lid magnets 98 in close proximity to power module sensor 286. The second lid
magnet 98 placed in registration with power module sensor 288. Here the "fully latched"
state is understood to be when the latch 62 is positioned to, as completely as designed,
prevent the unintended opening of the lid 62. Accordingly, the next time the evaluation
of the tool check state is performed, sensors 286 and 288 each assert a signal indicating
that a local magnetic field has been detected. Controller 320 interprets the signal
that even one magnet field is detected as indication that the power module has been
seated in the shell compartment and the lid 62 is fully latched. Controller 320 therefore
places the power module 180 in the latched state, step 338.
[0080] Upon placing the power module 180 in the latched state, the controller 320 initially
determines the type of handpiece to which the power module is attached. This determination,
in step 340, is made by determining which one of the sensors is asserting a signal
indicating the close presence of a magnet. There are three possible conditions: only
sensor 286 senses a magnetic; only sensor 288 senses a magnet; or both sensors 286
and 288 sense the presence of a magnet. Thus in this version of the invention, in
step 340, controller 320 determines to which one of three possible handpieces the
power module 180 is connected.
[0081] Based on the determination of step 340, in a step 342, the controller configures
the power module for operation. This may include selecting from preloaded data the
following operating characteristics of the motor: a maximum rotor speed; or current
draw. Thus for the rotary handpiece 40, the controller may configure the power module
so when a trigger is depressed a maximum amount the motor will run at a maximum speed
of 25,000 RPM. In step 342 the controller also configures the power module how to
operate as a function of the depression of one or both of the triggers. For example
for a first type of handpiece, it may be appropriate to configure the module so that
an indication that trigger 152 was depressed in an indication that the motor should
run in a forward direction and an indication that trigger 154 was depressed an indication
that the motor should run in a reverse direction. For a second type of handpiece an
indication that trigger 152 was depressed would again serve as an indication that
motor should run in the forward direction. For the second handpiece an indication
that trigger 154 was depressed serves as indication the motor should be run in an
oscillatory pattern.
[0082] Once controller 320 finishes configuring the module, the controller causes the module
to enter an active state, step 346. In the active state, the controller sourcing bias
current to sensors 302 and 304. Also, voltages are applied to all components internal
to the module that need to be turned on in order to actuate the motor 290. When power
module 180 is in the active state, the controller draws more current than when in
the tool check state. As represented by step 348, when the power module 180 is in
the active state, the controller 340 waits to determine if one of the triggers 152
or 154 has been depressed. This monitoring is performed monitoring the signals output
by sensors 302 and 304.
[0083] Once the power module 180 is in the active state, handpiece 30 is ready for use.
Prior to this time the appropriate front end attachment and device driven by the handpiece
are typically attached to the handpiece 40. Tool 30 is actuated by the depression
of the appropriate trigger 152 or 154. This causes the associated magnet 162 or 164,
respectively, to move towards the adjacent sensor 302 or 304, respectively. Sensors
302 and 304 output sensor signals representative of the extent to which the associated
magnets are depressed. Based on these signals and the previously loaded handpiece
type configuration instructions, the controller actuates the motor, step 354, to cause
the movement desired by the practitioner.
[0084] While the motor 270 is actuated, the power module controller continually monitors
the sensors 302 or 304, step 356. This monitoring is performed to determine if the
trigger 152 or 154 was released. The release of one of the depressed trigger 152 or
154, results in the change of the output signal from the associated sensor, 302 or
304, respectively. In response to this change in the sensor signal, controller 320,
in step 358 deactivates the motor. The controller then returns to step 348 to await
the next depression of the trigger.
[0085] Once the controller enters the tool check state, the controller continually monitors
sensors 286 and 288 determine if the signals asserted by these sensors change. In
Figure 17B, for ease of illustration, this is shown as a separate step 360 occurring
after step 358 is executed. Step 360 is essentially identical to step 334. This monitoring
is performed because, at some time, the latch may rotate away from the fully latched
state. Ideally, this event should only occur when the motor 290 is in a deactivated
state.
[0086] If, in step 360 the processor determines the change of the signals indicate that
the latch is moving away from the fully latched state and the motor is active, controller
320 initially deactivates the motor (step not shown). Regardless of whether or not
the motor is running when the latch is opened, the controller then returns the power
module to the sleep state, step 330. Then, as described above, steps 332 and 334 are
cyclically reexcuted to determine whether or not the power module 180 is properly
latched in a handpiece.
V. OPERATION WITH A DIFFERENT HANDPIECE
[0087] An alternative handpiece 360 that can be employed as the handpiece of tool 30 of
this invention is seen in Figure 18. Handpiece 360 includes a shell 362 with a base
364, a handgrip 366 and a barrel 368. Base 364, handgrip 366 and barrel 368 are similar
in shape and function to, respectively, the previously described base 44, handgrip
346 and barrel 48. A head 370 extends forward from the distal end of the barrel 368.
A blade mount 372 is rotatably mounted to the head 370. Blade mount 374 is configured
to releasably hold a sagittal saw blade 376. Blade 376 is understood to be the energy
applicator used with handpiece 360.
[0088] Internal to barrel 368 is a transmission assembly. This transmission assembly is
represented as a cylindrical phantom shaft 384. The transmission assembly converts
the rotary motion of the power module output shaft into a motion that pivots the blade
mount 372 around an axis. This axis is perpendicular to the proximal-to-distal longitudinal
axis through the barrel 368. Since blade 376 is pivotally mounted to the blade mount
the pivoting of the blade mount results in a like back and forth motion of the blade
376. The blade teeth thus reciprocate back and forth along an arc located forward
of the handpiece.
[0089] Handpiece 360 has a single trigger 385. Trigger 385 is analogous to trigger 154.
[0090] A lid 388 is hingedly secured to the open bottom end of shell base 364. Lid 364 is
essentially identical to previously described lid 62. To avoid redundancy the components
integral with lid 388 are not illustrated. There is one significant difference between
lids 62 and 364. Only a single magnet 98 is mounted to the latch knob 90 of lid 364.
Arbitrarily the magnet 98 mounted to lid 364 is the magnet the presence of which is
sensed by sensor 288.
[0091] A tool 30 of this invention that includes handpiece 360 is prepared for use the same
way a tool with handpiece 40 is prepared for use. After handpiece lid 388 is placed
in the full latched state, in step 340 only sensor 288 outputs a signal indicating
that a magnet was detected. In response to receipt of this signal magnet detected
signal from sensor 288, the controller 320 recognizes that the attached handpiece
type is of the type that includes sagittal saws.
[0092] Consequently, in step 342, the controller configured the tool for operation based
on this type of handpiece. Thus, in this version of the invention, this means the
controller configures the handpiece to operate so when the trigger is fully depressed
the maximum speed at which the handpiece will run the motor is 20,000 RPM. This is
different from the maximum speed at which the controller 320 will run the motor than
when handpiece 40 is detected.
[0093] Tool system 30 of this invention is thus configured so that upon the latching of
the power module 180 in a handpiece 40 or 360, the module controller 320 determines
that the power module 180 is both properly latched in place and the type of handpiece
in which the module is seated. Based on this later information the controller configures
the power module to operate correctly for that type of handpiece. This invention thus
eliminates the need for an individual to manual set the power module to the correct
operational setting for the type of handpiece. This invention does more than eliminate
the time required to perform this task. The invention eliminates the likelihood that
due to error the handpiece type data are incorrectly entered.
[0094] Still another version of this specific version of the invention is that the data
tag, the set of magnets, does more than provide an indication of handpiece. The absence/presence
of this magnets serves as an indication whether or not the lid is properly latched.
[0095] It is a further feature of this invention that the sensors 286 and 288 that detect
the proximity of the handpiece lid 62 and the trigger sensors 302 and 304 are spaced
at least 5 cm apart and more preferably at least 8 cm apart. This feature of the invention
reduces the likelihood that if a single magnet is somehow placed adjacent the power
module that this single magnet will cause fields to be detected by both sets of sensors.
If this event was to occur, it could result in the unintended actuation of the power
module.
[0096] Further some tools, as a very nature of their operation, undergo a high degree of
vibration. Under some circumstances, this vibration could cause the latch to move
away from the fully latched state. As described above with reference to step 360,
the tool system of this invention is further configured to continuously monitor whether
or not the latch is in the fully latched state. The termination of the activation
of the power generating unit or the inability to turn on the tool provides a cue to
the user that the latch may have moved from the fully latched state. This provides
the surgical personnel the opportunity to withdraw the tool from the sterile field
verify the lid is latched or relatch the lid 62. This substantially reduces the likelihood
that, as a result of the latch unlatching, the lid opens and the module falls out
handpiece. If this event were to occur in close proximity to the patient the power
module could contaminate the sterile field.
[0097] Still other advantages of tool 30 of this invention are associated with how the components
forming the system are manufactured. In the described version of the invention, the
cells 270 are in parallel. Each cell 270 is centered on a longitudinal axis that is
perpendicular to the longitudinal axis of the tower 210 and motor 290. Often the tower
210 and motor 290 have a common longitudinal axis. Further the cells 270 project outwardly
beyond the tower 210. This construction of the invention provides the module base
182 with a center of mass that is closer to the module bottom plate 184 than the head
214. This provides the module with stability when placed on a surface. By extension
this feature of the module as well as the module 180 serves to stabilize the tool
30 when the module 180 is in the handpiece 40 or 360 and resting of the tool lid 62.
[0098] A further feature of this invention is that both the contacts 266 over which a charging
current are applied to the cells 270 and the cells themselves are disposed in the
module base 182. A benefit of this feature of the invention is the conductors over
which the relatively high charging currents are sources from the contacts 266 to the
cells 270 only have to extend through the module base 182. There is no need go to
the expense of routing these contacts, through which charging current flows, through
the module tower 210.
[0099] Still a further feature of this invention is that contacts 266, cells 270, sensors
286 and 288 and controller 320 are mounted to a common circuit board 240. A benefit
of this feature of this invention is that once these components are mounted to the
circuit board 240, the circuit board can be fitted to the power module 180. This construction
facilitates the economical assembly of the power module.
VI. MAINTENANCE KEY
[0100] Figure 19 depicts how a maintenance key 424 can be fitted to a power module 180a
to place the power module in a maintenance mode. In Figure 19 the power module 120
is shown as being coupled to a charger 402. Charger 402 includes a shell 404 in which
the internal components of the charger are housed. The shell 404 is formed with a
bore 406 dimensioned to accommodate the power module tower 210. The specific charger
402 is designed to charge two power modules 180. Shell 404 is therefore formed with
two bores 406. Two sets of contacts 408 extend upwardly from the top surface of the
shell 404. When a power module 180a is seated on the charger 402 such that the module
tower is disposed in a bore 406, the charger contacts 408 extend through the openings
208 in the power module lid 206. The charger contacts 408 engage the power module
contacts 206 to provide the necessary conductive links between the power module 180
and the charger 404.
[0101] Not illustrated and not part of the present invention are the components internal
to the charger that source current to the cells 270 and provide other functions some
of which are described below. These other components include a power supply, a load
resistor and a processor. The components inside chargers are disclosed in US Pats.
No.
6,018,227 and No.
6,564,242, each of which is incorporated herein by reference. Seen on the outside of the shell
are buttons 412 and a display 418. Buttons 412 are the control members that are depressed
to control the charging process. Display 418 is the component of the charger 402 on
which images are presented that provide information about the charging process and
the state of the power module 180a.
[0102] The maintenance key 424 is a component that is placed on the power module 180 when
the power module is attached to the charger 402. The maintenance key 424 is placed
on the power module when the person handling the power module wants to do more than
simply recharge the cells. The body of maintenance key 424 is a plate 426 designed
to extend over at least some of if not all of the power module bottom plate. A rim
427, the portion of the maintenance key below the dashed line, extends downwardly
from and circumferentially around the outer perimeter of key plate 426. Rim 427 extends
around the outside of the power module side, front and back panels 186, 88, and 190,
respectively, so as to removably hold the key 42 static to the power module 180a.
[0103] Internal to the plate 426 are two magnets 428, represented by phantom cylinders.
Magnets 428 are positioned so that when key 424 is seated over the power module 180
one magnet is disposed over sensor 286 and the second magnet is disposed over sensor
288.
[0104] A power module 180a is identical in structure to previously described power module
180. Power module 180a of this version of the invention has four operating states.
The first state is when neither sensor 286 nor sensor 288 assert a signal indicating
the presence of a nearby magnet. When this condition exists, controller 320 recognizes
that the power module is being in the state in which the module is not in a fully
latched handpiece. The second and third states are when just one of the sensors 286
or 288 asserts a signal indicating a magnet is nearby. When this condition exists
the controller 320 recognizes the power module as being in a fully latched handpiece
and connected to either a first type of handpiece (the second state) or a second type
of handpiece (the third state).
[0105] The fourth state is when the sensors 286 and 288 assert signals indicating that a
magnet is adjacent both sensors. The power module 180a is in this state only when
key 424 is fitted over the module base 184. When this condition exists, the controller
320 recognizes the power module 180a is being in a maintenance state. When power module
180a is in the maintenance state, the controller writes out to the charger 402, information
regarding the operating history of the module.
[0106] Power module 180a operates in the same general manner in which power module 180 operates
as described with reference to Figures 17A and 17B. When the power module 180a is
placed on the charger 402 the placing of the key 424 on the module bottom plate 184,
in step 334, cause the controller to initially interpret the module as being in a
handpiece that is fully latched. In the evaluation of step 340 the controller 320,
based on the signals from both sensors 286 and 288 recognizes that the module is not
in a handpiece but has rather been placed in a maintenance mode.
[0107] Once the power module 180 recognizes that the module is not in a handpiece, steps
342-360 are not executed. Instead, the controller 320 writes out the data stored in
the memory integral with the memory. These data are written out to the processor integral
with the charger 402 using a process not part of the present invention. These data
depending on the structure of the charger may be available for presentation on the
display 412 or for storage in a device remote from the charger 402.
[0108] A benefit of the above arrangement is that it provides a means to place the power
module 180a in the maintenance mode without requiring the entry of special data.
[0109] Once in the maintenance mode data can, if necessary, be uploaded into the power module
controller 320. These data include updated instructions for controlling the operation
of the module power generating unit.
VII. ALTERNATIVE EMBODIMENTS
[0110] The above is directed to specific versions of the invention. Alternative versions
of the invention may have features different from what is described above.
[0111] It should be understood that for one or more specific types of handpieces there are
several sub-types of the handpiece. Thus a single trigger saw type handpiece may include
both a saw that is a sagittal saw and a second saw, a reciprocating saw.
[0112] For example, there is no requirement that in all versions of the invention magnets
function as the data tags that indicate the type of handpiece to which the power module
is connected. In one alternative version of the invention, the data tag integral with
the handpiece are RFID tags. In this version of the invention, the data reader is
a circuit integral with the power module capable of reading the RFID tags. Collectively,
these components are mounted so that the reader can only read the RFID tag when the
handpiece latch is in the locked state. In this version of the invention, when the
power module is in the tool check state, the controller integral with the module temporarily
actuates the RFID reader. The reader broadcasts an basic interrogation signal and
waits for response. The absence of a response to this basic interrogation signal is
interpreted as an indication that the power module is not seated in a handpiece with
a properly latched lid. A response to the basic interrogation signal is interpreted
by the controller as an indication that the power module is disposed in a properly
latched handpiece. If the tool system is in this state, the power module controller
causes the data in the RFID tag to be read out. These data include the handpiece type
data used in step 342 to configure the tool for the specific handpiece type.
[0113] In some other versions of the invention, the data tag is a bar code. In these versions
of the invention the reader is a device integral with the power module capable of
reading the bar code. In still other versions of the invention, the data tag is a
NOVRAM or EEPROM. In these versions of the invention, the data reader may include
contacts integral with the power module. These contacts come into contact with complementary
contacts integral with the handpiece that are connected to the NOVRAM or EEPROM. In
these versions of the invention, the process of determining whether or not the power
module is in a properly latched handpiece and the type of handpiece similar to the
steps described above with respect to when the data tag is an RFID tag.
[0114] In some versions of the invention, the components used to determine whether or not
the power module is in a fully latched handpiece and the data tag/data reader are
separate from each other. For example, in one embodiment of this version of the invention,
a magnet mounted to the latch may serve as the component that is sensed to determine
whether or not the power module is in a handpiece that has been properly latched.
In this version of the invention, another component such as an RFID tag or bar code
functions as the data tag.
[0115] In still another version of this invention a single magnet serves both as the data
tag and the component that indicates whether or not the power module is seated in
a properly latched handpiece. In these versions of the invention, the sensor that
monitors the strength of the sensed magnetic field generates a signal that varies
as a function of the magnitude of the magnetic field. In this version of the invention,
a single magnet is mounted to the handpiece. The strength of the magnet is selected
as a function of the type of handpiece. In this version of the invention, the controller
interprets a signal from the sensor indicating that a magnetic field is present as
an indication that the power module is contained in a properly latched handpiece.
The controller then determines the type of the handpiece based on the strength of
the magnetic field.
[0116] In other versions of the invention in which plural magnets function as the data tag,
the handpiece may have more than two magnets. For example, in some versions of the
invention, the handpiece may have up to four magnets that are employed to indicate
handpiece type. In this version of the invention, the power module data reader would
consists of sensors able to determine the presence/absence of each of these magnets.
Thus in this version of the invention, assuming the magnets also provide the data
indicating whether or not the lid is properly latched, this version of the invention
could provide data indicating which one of up to 15 different types of handpieces
is coupled to the power module. In this version of the invention, each of the magnets
may not be on lid knob. In this version of the invention, two or the magnets may be
attached to the lid knob. The remaining magnets are, if present, attached to the lid.
Thus, in this version of the invention, the presence/absence of the lid knob-mounted
magnets are attached to the lid knob are used to provide an indication of both the
lid being latched and some data regarding handpiece type. The presence/absence of
the remaining magnets are used to provide the rest of the handpiece-type data.
[0117] It should likewise be understood that the power generating unit may be different
from the described motor. Thus in some versions of the invention, the power generating
unit may be device that outputs an RF signal. In these versions of the invention,
the handpiece includes an electrode that services the conductive member over which
the RF signal is applied to a site on the patient. Based on the data tag associated
with the handpiece, the controller integral with this power module may set one or
more of the following characteristics of the RF signal; frequency; pulse duty cycle;
voltage; current; or waveform shape.
[0118] In other version of the invention, the power generating unit is a transducer that
vibrates. In these versions of the invention, the handpiece includes a tip. The tip
is the component of the tool through which the vibrations of the transducer are applied
to tissue. In these versions of the invention, based on the handpiece type data, the
controller integral with the power module is able to set at least one of the following:
frequency of transducer vibrations; duty cycle of vibrations; or voltage and current
of the drive signal applied to the transducer.
[0119] Other power modules may include power generating units that emit heat (thermal energy)
or light (photonic) energy. Each of these different power modules can be used with
different plural types of handpieces. Each handpiece has specific type of applicator
that is used to apply the energy to tissue in order to accomplish a specific medical
or surgical task.
[0120] Similarly, there is no requirement that all tools of this invention be pistol shaped
like illustrated handpieces 40 and 360. In alternative versions of the invention,
the handpiece may have elongated pen or pointer like shape. In other versions of the
invention, the geometric features with which the handpiece and power module are provided
to ensure that these components are properly aligned may differ from what has been
described. Thus in one version of the invention, the handpiece shell and the power
module may both be generally cylindrical in shape. In this version of the invention,
the interior of the handpiece shell or housing may have a single rib or groove. The
associated power module shell is formed with a complementary groove that accommodates
the rib or a complementary rib that seats in the groove.
[0121] The components integral with different versions of the invention may have features
different from what has been described. For example, in some versions of the invention,
the latch, instead of rotating may move longitudinally. In versions of the invention
where it is critical to sense the presence/strength of magnetic fields sensors other
than Hall sensors may be employed. These sensors include reed switches.
[0122] Likewise other sensing assemblies may be incorporated into alternative versions of
the invention to determine whether or not the user actuated control member has been
depressed. For example, in some versions of the invention, internal to the power module
is a variable resistor. The wiper that sets the resistance is set by the control member
integral with the handpiece.
[0123] In versions of the invention wherein the trigger displaces a magnet, there may be
two sensors associated with each magnet. In these versions of the invention, the sensors
may serve a redundancy purpose. Alternatively, in these versions of the invention,
the power module is configured to when in the latched state, activate the low powered
one of the sensors. When the signal from this sensor indicates the associated trigger
was depressed, the controller places the power module then enters the active state.
When the power module is in the active state, the higher power-consuming sensor is
actuated. The signal from this second sensor is what causes the controller 320 to
selectively actuate the handpiece power generating unit.
[0124] Also, it is within the scope of this invention, that the handpiece be constructed
of components that can be sterilized upon manufacture but not resterilized. This handpiece
may be useful in the event manufacturing economics make it less costly to provide
a use once handpiece than a handpiece formed out of components that must be able to
withstand the rigors of the sterilization process.
[0125] Likewise the process steps executed by other versions of this invention may differ
from what has been described. For example, there may be a version of this invention
where the control components will not over an extended period of time of several days
or more appreciably drawn down the charge in the cells. In this version of the invention
it may not be necessary to conserve power by cycling the power module between a power
saving sleep state and the other states in which a greater quantity of charge is drawn.
[0126] In some versions of the invention the energy applicator that extends from the handpiece
may be part of the handpiece. One type of handpiece that would have this structure
would be an ultrasonic handpiece. In this type of handpiece, the vibrating tip, may
be integrally built into the shell portion of the handpiece. A second type of handpiece
that could have this structure is an RF ablation tool. This type of handpiece would
thus be constructed so the electrode that serves as the device over which the energy
output by the power generator is applied to the tissue is against built into the shell
portion of the handpiece. Handpieces of these versions of the invention therefore
do not including coupling assemblies that removably hold the energy applicator to
the rest of the handpiece.
[0127] In some versions of the invention that rely on a key to place the power module in
the maintenance mode, the physical key 424 may be only one component that is needed
to place the power module in the maintenance mode. In other versions of the invention,
processor 320 must determine that plural conditions exist before it places the power
module in the maintenance mode. For example, the processor may only place the power
module 180a in the maintenance mode when the processor determines (1) the power module
is attached to the charger 402 and (2) the physical key is in place. Thus, this version
of the invention is constructed so the power module will only enter the maintenance
mode when the module is attached to a charger 402. Processor 320 makes this determination
by monitoring the signal present at one of the contacts 266 integral with the power
module 180a. This may be the contact 266 over which current is sourced to the cells
270. Alternatively, this may be a contact 266 over which a flag signal or a data signal
is received when the power module 180a is connected to the charger.
[0128] A benefit of this construction of the invention is that ensures that the power module
only enters the maintenance mode when the module is attached to the charger. A second
benefit of this construction of the invention is that the set of signals that indicate
that power module is the maintenance mode can have two functions. Specifically, when
the controller 320 receives the signals and without an indication that current is
being sourced, the controller can interprets the power module being latched in a specific
type of handpiece. When the controller receives the signals with the indication that
current is being sourced, the controller can interpret the power module as being attached
to the charger and the individual performing the charging wants the power module placed
in the maintenance mode.
[0129] The features of the various versions of the invention can be combined as necessary.
[0130] Thus, it is an object of the appended claims to cover all such variations and modifications
that come within the true spirit and scope of this invention.
[0131] The following examples are also encompassed by the present disclosure and may fully
or partly be incorporated into embodiments. The reference numerals serve for illustration
purposes only and are not intended to limit the examples to what is shown in the drawings.
Example 1. A surgical handpiece (40) including:
a shell (42), said shell shaped to define a void (52) for receiving a power module
(180) and an opening through which the power module is inserted into and removed from
the void space;
an energy applicator (376) attached to said shell, said energy applicator configured
to when actuated output energy for application to a tissue to perform a medical/surgical
task;
a transmission component (372) disposed in said shell for transmitting energy output
by the power module to said energy applicator;
a lid (62) moveably mountable to the shell to cover the shell opening; and
a latch (90, 101) moveably attached to one of the shell or the lid for holding said
lid in a latched state;
characterized in that,
a data tag (98) is mounted to the latch (90, 101) so as to move with said latch, the
data element including data that identifies said handpiece.
Example 2. The surgical handpiece (40) of Example 2, wherein:
the shell (42) is shaped to have a base (44); a grip (46) that extends upwardly from
said base and a barrel (48) that is disposed over said grip; the base and grip defining
the shell void (52), the base having the opening through which the power module (180)
is inserted and removed;
the energy applicator (376) extends forward from said barrel; and
the lid (62) is moveably attached to the shell base (44) to cover the shell opening.
Example 3. The surgical handpiece (40) of Examples 1 to 2, wherein a coupling assembly
(170) is mounted to said shell to removably hold the energy applicator (376) to the
shell (42).
Example 4. The surgical handpiece (40) of any one of Examples 1 to 3, wherein said
energy applicator (376) is configured to one of: be rotated; be oscillated; be vibrated;
receive and apply RF energy; receive and apply thermal energy; receive and apply photonic
energy.
Example 5. The surgical handpiece (40) of any one of Examples 1 to 4, wherein said
data tag (98) is one from the group consisting of: a set of magnets; an RFID tag;
a memory; a bar code.
Example 6. The surgical handpiece (40) of any one of Examples 1 or 5, wherein the
latch (90, 101) is moveably attached to said lid (62).
Example 7. The surgical handpiece (40) of any one of Examples 1 to 6, wherein the
latch (90, 101) is rotatably mounted to one of the shell (42) or the lid (62).
Example 8. The surgical handpiece (40) of any one of Examples 1 to 7, wherein the
lid (62) is hingedly attached to the shell (42).
Example 9. A power module (180) for providing rotational energy to the surgical handpiece
(40) of any one of Examples 1 to 8, so the handpiece (40) applies the energy to an
energy applicator (376) or a medical implant, said power module comprising:
a shell (182, 204), said shell shaped to have: a base (182) with a bottom plate (184),
the base subtending a cross sectional area; a tower (210) that extends upwardly from
the base, the tower subtending a cross sectional area less than that of said base;
a motor (290) disposed in said shell tower, said motor having an output shaft (294)
that is accessible through an opening in said shell tower;
at least one cell (270) disposed in said shell base, said cell capable of storing
charge for energizing said motor;
a first set of sensors (286, 288) disposed in said shell base adjacent said bottom
plate for detecting the presence of magnetic fields generated external to said shell,
said first set of sensors generating first sensor signals based on the sensed magnetic
fields;
a second set of sensors (302, 304) disposed in said shell tower (210) for detecting
the presence of magnetic fields generated external to said shell, said second set
of sensors generating second sensor signals based on the sensed magnetic fields, wherein
said first set of sensors and said second set of sensors are spaced at least 5 cm
apart from each other; and
a controller (320) disposed in said shell that selectively connects said at least
one cell to said motor for actuating said motor, said controller further configured
to: receive the first sensor signals; receive the second sensor signals; and based
on the received sensor signals regulate the application of current from said at least
one cell to said motor so as to control the actuation of said motor.
Example 10. The power module (180) of Example 9, wherein said shell is further formed
so that: said base (182) has a center; and said tower (210) extends upwardly from
said base along an axis that is spaced away from the center of said base.
Example 11. The power module (180) of Examples 9 or 10, wherein said first set of
sensors include plural sensors (286, 288).
Example 12. The power module (180) of any one of Examples 9 to 11, wherein said second
set of sensors include plural sensors (302, 304).
Example 13. The power module (180) of any one of Examples 9 to 12, wherein:
said tower (210) is shaped to define a recess (229);
said second set of sensors (302, 304) are disposed in the recess formed in said tower;
and
a plate (310) formed from magnetically permeable material is disposed over the tower
recess so as to cover said second set of sensors.
Example 14. The power module (180) of any one of Examples 9 to 13 wherein said shell
tower (210) is shaped to have: a bore (216) that extends downwardly from a top portion
of said tower, the bore being the opening through which the motor output shaft is
accessible; and a slot (218) that extends inwardly from a panel of said tower into
said bore, the slot extending downwardly from the top of the said tower.
Example 15. The power module (180) of any one of Examples 9 to 14, wherein said controller
(320) is further configured to:
based on the first sensor signals, determine a specific type of handpiece to which
said power module is attached (340), the specific type of handpiece being one from
a plurality of different types of handpieces; and
based on the type of handpiece to which said power module is attached and the second
sensor signals, selectively actuate said motor so that said motor is actuated specifically
for the type of handpiece to which said power module is attached (342, 354).
Example 16. The power module (180) of Example 15, wherein said controller (320) is
further configured to, based on the type of handpiece to which said power module is
attached, selectively regulate at least one of: the maximum speed of the motor; or
how the motor is actuated in response to receipt of a specific second signal.
Example 17. A power module (180) for providing rotational energy to a surgical handpiece
that applies the energy to an energy applicator or a medical implant, said power module
comprising:
a shell, said shell being formed to have: a base (182); a tower (210) that extends
upwardly from the base; and a first opening in the tower;
a motor (290) disposed in said tower so as to have longitudinal axis that extends
upwardly from the shell base, said motor having an output shaft that is accessible
through the shell first opening;
at least one recharagable cell (270) disposed in the shell base, said cell capable
of storing charge for energizing said motor; and
at least one contact (266) disposed in the shell that is accessible through the shell,
said at least one contact being connected to said at least one cell so that charging
current is applied to said cell from said contact; and
a controller disposed in the shell that selectively connects said at least one cell
to said motor for actuating said motor
characterized in that,
the shell is further formed so that the base (182) is rectangular in shape and has
a top plate (206) and opposed proximal and distal ends and the tower (210) that extends
upwardly from said top plate, the tower being located closer to the distal end of
the base than the proximal end and the shell has at least one second opening (208)
located in said top plate adjacent the proximal end of the base;
the at least one rechargeable cell (270) is disposed in the shell base so as to have
a longitudinal axis that is perpendicular to the longitudinal axis of said motor;
and
the at least one contact (266) is located in the shell base so as to be accessible
through the at least one second opening (208) of the shell.
Example 18. The power module (180) of Example 17, wherein:
a first set of sensors (286, 288) disposed in the shell base adjacent said bottom
plate (184) for detecting the presence of magnetic fields generated external to said
shell, said first set of sensors generating first sensor signals based on the sensed
magnetic fields;
a second set of sensors (302, 304) disposed in said shell tower (210) for detecting
the presence of magnetic fields generated external to said shell, said second set
of sensors generating second sensor signals based on the sensed magnetic fields, wherein
said first set of sensors and said second set of sensors are spaced at least 5 cm
apart from each other; and
said controller (320) is further configured to: receive the first sensor signals;
receive the second sensor signals; and based on the received sensor signals regulate
the application of current from said at least one cell to said motor so as to control
the actuation of said motor.
Example 19. The power module (180) of Example 18, wherein said controller (320) is
further configured to:
based on the first sensor signals, determine a specific type of handpiece to which
said power module is attached (340), the specific type of handpiece being one from
a plurality of different types of handpieces; and
based on the type of handpiece to which said power module is attached and the second
sensor signals, selectively actuate said motor so that said motor is actuated specifically
for the type of handpiece to which said power module is attached (342, 354).
Example 20. The power module of Example 19, wherein said controller (320) is further
configured to, based on the type of handpiece to which said power module is attached,
selectively regulate at least one of: the maximum speed of the motor; or how the motor
is actuated in response to receipt of a specific second signal.
Example 21. The power module of any one of Examples 18 to 20, wherein said first set
of sensors consists of a plurality of sensing elements (286, 288).
Example 22. The power module of any one of Examples 18 to 21, wherein said second
set of sensors consists of a plurality of sensing elements.
Example 23. The power module of any one of Examples 17 to 22, wherein a circuit board
(240) is disposed in said shell base and said at least one cell, said at least one
contact (266) and said controller (320) are mounted to said circuit board.
Example 24. A power module (180) for providing rotational energy to a surgical handpiece
that applies the energy to an energy applicator or a medical implant, said power module
comprising:
a shell, said shell being formed to have: a base (182); and a tower (210) that extends
upwardly from the base; a first opening (210) in the shell tower;
a motor (290) disposed in said tower so as to have longitudinal axis that extends
upwardly from the shell base, said motor having an output shaft that is accessible
through the shell first opening;
at least one rechargeable cell (270) disposed in the shell base, the cell capable
of storing charge for energizing said motor;
at least one contact (266) located in said shell, said at least one contact being
connected to said at least one cell so that charging current is applied to said cell
from said contact; and
a controller (320) disposed in the shell that selectively connects said at least one
cell to said motor for actuating said motor
characterized in that:
the shell is further formed so that the base (182) is rectangular in shape and has
opposed bottom and top plates (184, 206) and opposed proximal and distal ends; the
tower that extends upwardly from said top plate, said tower being located closer to
the distal end of the base than the proximal and at least one second opening (208)
located in said top plate adjacent the proximal end of said base;
a first set of sensors (286, 288) disposed in the shell base (182) adjacent the shell
bottom plate for detecting the presence of magnetic fields generated external to said
shell, said first set of sensors generating first sensor signals based on the sensed
magnetic fields;
a second set of sensors (302, 304) disposed in the shell tower for detecting the presence
of magnetic fields generated external to said shell, said second set of sensors generating
second sensor signals based on the sensed magnetic fields, wherein said first set
of sensors and said second set of sensors are spaced at least 5 cm apart from each
other;
the controller (320) is further configured to: receive the first sensor signals; receive
the second sensor signals; and based on the received sensor signals regulate the application
of current from said at least one cell to said motor so as to control the actuation
of said motor; and
a circuit board (240) in the shell base (182), wherein said at least one cell (270),
said at least one contact (266), said first set of sensors (286, 288) and said controller
(320) are mounted to said circuit board and said circuit board is disposed in the
shell base and said at least one contact is mounted to said circuit board so that
said at least one contact is accessible through the at least one second opening (208)
in said shell.
Example 25. The power module (180) of Example 24, wherein said at least one cell (270)
is mounted in the shell base so as to extend outwardly from the shell tower.
Example 26. The power module (180) of Examples 24 or 25, wherein said controller (320)
is further configured to:
based on the first sensor signals, determine a specific type of handpiece to which
said power module is attached (340), the specific type of handpiece being one from
a plurality of different types of handpieces; and
based on the type of handpiece to which said power module is attached and the second
sensor signals, selectively actuate said motor so that said motor is actuated specifically
for the type of handpiece to which said power module is attached (342, 354).
Example 27. The power module (180) of Example 26, wherein said controller is further
configured to, based on the type of handpiece to which said power module is attached,
selectively regulate at least one of: the maximum speed of the motor; or how the motor
is actuated in response to receipt of a specific second signal.
Example 28. The power module (180) of any one of Examples 24 to 27, wherein said shell
is further formed so that: said base (182) has a center; and said tower (210) extends
upwardly from said base along an axis that is spaced away from the center of said
base.
Example 29. The power module (180) of any one of Examples 24 to 28, wherein said first
set of sensors include plural sensors (286, 288).
Example 30. The power module (180) of any one of Examples 24 to 29, wherein said second
set of sensors include plural sensors (302, 304).
Example 31. The power module (180) of any one of Examples 24 to 30, wherein:
the shell tower (210) is shaped to define a recess (229);
said second set of sensors (302, 304) are disposed in the recess formed in said tower;
and
a plate (310) formed from magnetically permeable material is disposed over the tower
recess so as to cover said second set of sensors.